Launch from Cape Canaveral (KSC); landing on Edwards AFB. Number one main engine shutdown prematurly, resulting in an Abort To Orbit (ATO) trajectory (planned orbit was 400 km). The countdown for a planned launch on July 12, 1985 had been halted at T-3 seconds after main engine ignition when a malfunction of number two Space Shuttle Main Engine (SSME) coolant valve caused shutdown of all three main engines. Launch took place at July 29, 1985 after a delay of one hour, 37 minutes due to a problem with the table maintenance block update uplink.

Third flight of Spacelab (Mission SL-2); first time of testing "Instrument Pointing System" (IPS) in orbit, which was developed by Dornier Corporation. Deploying and retrieving of platform PDB. Experiments in life sciences, plasma physics, astronomy, high energy astrophysics, solar and atmospheric physics and technical research. The mission was extended one day for additional payload activities.